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1.
J Cardiothorac Surg ; 19(1): 258, 2024 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-38643131

RESUMEN

BACKGROUND: Patients with severe aortic stenosis (AS) and left ventricular (LV) dysfunction demonstrate improvement in left ventricular injection fraction (LVEF) after aortic valve replacement (AVR). The timing and magnitude of recovery in patients with very low LVEF (≤ 25%) in surgical or transcatheter AVR is not well studied. OBJECTIVE: Determine clinical outcomes following transcatheter aortic valve replacement (TAVR) and surgical aortic valve repair (SAVR) in the subset of patients with severely reduced EF ≤ 25%. METHODS: Single-center, retrospective study with primary endpoint of LVEF 1-week following either procedure. Secondary outcomes included 30-day mortality and delayed postprocedural LVEF. T-test was used to compare variables and linear regression was used to adjust differences among baseline variables. RESULTS: 83 patients were enrolled (TAVR = 56 and SAVR = 27). TAVR patients were older at the time of procedure (TAVR 77.29 ± 8.69 vs. SAVR 65.41 ± 10.05, p < 0.001). One week post procedure, all patients had improved LVEF after both procedures (p < 0.001). There was no significant difference in LVEF between either group (TAVR 33.5 ± 11.77 vs. SAVR 35.3 ± 13.57, p = 0.60). Average LVEF continued to rise and increased by 101% at final follow-up (41.26 ± 13.70). 30-day mortality rates in SAVR and TAVR were similar (7.4% vs. 7.1%, p = 0.91). CONCLUSION: Patients with severe AS and LVEF ≤ 25% have a significant recovery in post-procedural EF following AVR regardless of method. LVEF doubled at two years post-procedure. There was no significant difference in 30-day mortality or mean EF recovery between TAVR and SAVR. TRIAL REGISTRATION: Indiana University institutional review board granted approval for above study numbered 15,322.


Asunto(s)
Estenosis de la Válvula Aórtica , Implantación de Prótesis de Válvulas Cardíacas , Reemplazo de la Válvula Aórtica Transcatéter , Disfunción Ventricular Izquierda , Humanos , Válvula Aórtica/cirugía , Reemplazo de la Válvula Aórtica Transcatéter/métodos , Volumen Sistólico , Estudios Retrospectivos , Implantación de Prótesis de Válvulas Cardíacas/métodos , Resultado del Tratamiento , Factores de Riesgo
2.
J Cardiovasc Pharmacol ; 83(3): 251-257, 2024 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-38086077

RESUMEN

ABSTRACT: Unfractionated heparin is the most common anticoagulant used during percutaneous coronary intervention. Practice guidelines recommend an initial weight-based heparin bolus dose between 70 and 100 U/kg to achieve target activated clotting time (ACT) of 250-300 seconds. The impact of severe obesity on weight-based heparin dosing is not well studied. We performed a retrospective analysis of 424 patients undergoing percutaneous coronary intervention who received heparin for anticoagulation. We collected detailed data on cumulative heparin administration and measured ACT values in this cohort. We performed separate analyses to identify clinical predictors that may affect dose-response curves. There was significant variability in dosing with mean dose of 103.9 ± 32-U/kg heparin administered to achieve target ACT ≥ 250 seconds. Women received higher initial heparin doses when adjusted for weight than men (97.6 ± 31 vs. 89 ± 28 U/kg, P = 0.004), and only 49% of patients achieved ACT ≥ 250 s with the initial recommended heparin bolus dose (70-100 U/kg). Lower heparin dose (U/kg) was required in obese patients to achieve target ACT. In multivariate linear regression analysis with ACT as dependent variable, after inclusion of weight-based dosing for heparin, body mass index was the only significant covariate. In conclusion, there is significant variability in the therapeutic effect of heparin, with a lower weight-adjusted heparin dose required in obese patients.


Asunto(s)
Heparina , Intervención Coronaria Percutánea , Masculino , Humanos , Femenino , Heparina/efectos adversos , Estudios Retrospectivos , Anticoagulantes , Intervención Coronaria Percutánea/efectos adversos , Obesidad/diagnóstico , Obesidad/tratamiento farmacológico
3.
J Soc Cardiovasc Angiogr Interv ; 1(5): 100370, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-39131476

RESUMEN

Background: Femoral arterial access remains widely used despite recent increase in radial access for cardiac catheterization and percutaneous coronary intervention (PCI). Various femoral artery closure devices have been developed and are commonly used to shorten vascular closure times, with variable rates of vascular complications observed in clinical trials. We sought to examine the rates of contemporary outcomes during diagnostic catheterization and PCI with the most common femoral artery closure devices. Methods: We identified patients who had undergone either diagnostic catheterization alone (n = 14,401) or PCI (n = 11,712) through femoral artery access in the Indiana University Health Multicenter Cardiac Cath registry. We compared outcomes according to closure type: manual compression, Angio-Seal, Perclose, or Mynx. Access complications and bleeding outcomes were measured according to National Cardiovascular Data â€‹Registry standard definitions. Results: The use of any vascular closure device as compared to manual femoral arterial access hold was associated with a significant reduction in vascular access complications and bleeding events in patients who underwent PCI. No significant difference in access-site complications was observed for diagnostic catheterization alone. Among closure devices, Perclose and Angio-Seal had a lower rate of hematoma than Mynx. Conclusions: The use of femoral artery access closure devices is associated with a reduction in vascular access complication rates as compared to manual femoral artery compression in patients who undergo PCI.

4.
Future Cardiol ; 17(8): 1307-1311, 2021 11.
Artículo en Inglés | MEDLINE | ID: mdl-33615872

RESUMEN

We describe a unique case of fulminant myocarditis in a patient with presumed SARS-CoV-2 reinfection. Patient had initial infection 4 months backand had COVID-19 antibody at the time of presentation. Endomyocardial biopsy showed lymphocytic myocarditis, that is usually seen in viral myocarditis. The molecular diagnostic testing of the endomyocardial biopsy for cardiotropic viruses was positive for Parvovirus and negative for SARS-CoV-2. Authors highly suspect co-infection of SARS-CoV-2 and Parvovirus, that possibly triggered the immune cascade resulting in fulminant myocarditis. Patient was hemodynamically unstable with ventricular tachycardia and was supported on VA ECMO and Impella CP. There was impressive recovery of left ventricular function within 48 h, leading to decannulation of VA ECMO in 72 h. This unique case was written by the survivor herself.


Asunto(s)
COVID-19 , Coinfección , Miocarditis , Coinfección/diagnóstico , Humanos , Miocarditis/diagnóstico , Miocarditis/terapia , Reinfección , SARS-CoV-2
6.
TH Open ; 2(2): e173-e181, 2018 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-30882064

RESUMEN

BACKGROUND: High plasma fibrin clot strength (MA) measured by thrombelastography (TEG) is associated with increased risk of cardiac events after percutaneous coronary interventions (PCIs). Factor XIIIa (FXIIIa) cross-links soluble fibrin, shortens clot formation time (TEG-K), and increases final clot strength (MA). METHODS: We analyzed platelet-poor plasma from patients with previous PCI. Kaolin-activated TEG (R, K, MA) in citrate platelet-poor plasma and FXIIIa were measured (n = 257). Combined primary endpoint was defined as recurrent myocardial infarction (MI) or cardiovascular death (CVD). Relationship of FXIIIa and TEG measurements on cardiac risk was explored. RESULTS: FXIIIa correlated with TEG-MA (p = 0.002) and inversely with TEG-K (p < 0.001). High MA (≥35.35 mm; p = 0.001), low K (<1.15 min; p = 0.038), and elevated FXIIIa (≥83.51%; p = 0.011) were associated with increased risk of CVD or MI. Inclusion of FXIIIa activity and low TEG-K in risk scores did not improve risk prediction as compared with high TEG-MA alone. CONCLUSION: FXIIIa is associated with higher plasma TEG-MA and low TEG-K. High FXIIIa activity is associated with a modest increase in cardiovascular risk after PCI, but is less sensitive and specific than TEG-MA. Addition of FXIIIa does not provide additional risk stratification beyond risk associated with high fibrin clot strength phenotype measured by TEG.

8.
Clin Pharmacol ; 8: 45-50, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27350760

RESUMEN

BACKGROUND: Reloading with high-dose atorvastatin shortly before percutaneous coronary interventions (PCIs) has been proposed as a strategy to reduce periprocedural myonecrosis. There has been a concern that statins that are metabolized by cytochrome P450 3A4 may interfere with clopidogrel metabolism at high doses. The impact of simultaneous administration of high doses of atorvastatin and clopidogrel on the efficacy of platelet inhibition has not been established. METHODS: Subjects (n=60) were randomized to receive atorvastatin 80 mg together with clopidogrel 600 mg loading dose (n=28) versus clopidogrel 600 mg alone (n=32) at the time of PCI. Platelet aggregation was measured at baseline, 4 hours after clopidogrel loading dose, and 16-24 hours after clopidogrel loading dose by light transmittance aggregometry using adenosine diphosphate as agonist. RESULTS: Platelet aggregation was similar at baseline in both the atorvastatin and the control groups (adenosine diphosphate 10 µM: 57%±19% vs 61%±21%; P=0.52). There was no significant difference in platelet aggregation between the atorvastatin and the control groups at 4 hours (37%±18% vs 39%±21%; P=0.72) and 16-24 hours post-clopidogrel loading dose (35%±17% vs 37%±18%; P=0.75). No significant difference in incidence of periprocedural myonecrosis was observed between the atorvastatin and control groups (odds ratio: 1.02; 95% confidence interval 0.37-2.8). CONCLUSION: High-dose atorvastatin given simultaneously with clopidogrel loading dose at the time of PCI does not significantly alter platelet inhibition by clopidogrel. Statin reloading with high doses of atorvastatin at the time of PCI appears to be safe without adverse effects on platelet inhibition by clopidogrel (ClinicalTrials.gov: NCT00979940).

9.
Catheter Cardiovasc Interv ; 86(1): 136-43, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25510238

RESUMEN

BACKGROUND: Inaccurate aortic valve sizing and selection is linked to paravalvular leakage in transcatheter aortic valve replacement (TAVR). Here, a novel sizing valvuloplasty conductance balloon (SVCB) catheter is shown to be accurate, reproducible, unbiased, and provides real-time tool for aortic valve sizing that fits within the standard valvuloplasty procedure. METHODS AND RESULTS: The SVCB catheter is a valvuloplasty device that uses real-time electrical conductance measurements based on Ohm's Law to size the balloon opposed against the aortic valve at any given inflation pressure. Accuracy and repeatability of the SVCB catheter was performed on the bench in phantoms of known dimension and ex vivo in three domestic swine aortic annuli with comparison to computed tomography (CT) and dilator measurements. Procedural workflow and safety was demonstrated in vivo in three additional domestic swine. SVCB catheter measurements had negligible bias or error for bench accuracy considered as the gold standard (Bias: -0.11 ± 0.26 mm; Error: 1.2%), but greater disagreement in ex vivo versus dilators (Bias: -0.3 ± 1.1 mm; Error: 4.5%), and ex vivo versus CT (Bias: -1.0 ± 1.6 mm; Error: 8.7%). The dilator versus CT accuracy showed similar agreement (Bias: -0.9 ± 1.5 mm; Error: 7.3%). Repeatability was excellent on the bench (Bias: 0.02 ± 0.12 mm; Error: 0.5%) and ex vivo (Bias: -0.4 ± 0.9 mm; Error: 4.6%). In animal studies, the device fit well within the procedural workflow with no adverse events or complications. CONCLUSIONS: Due to the clinical relevance of this accurate, repeatable, unbiased, and real-time sizing measurement, the SVCB catheter may provide a useful tool prior to TAVR. These findings merit a future human study.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Válvula Aórtica/cirugía , Valvuloplastia con Balón/instrumentación , Prótesis Valvulares Cardíacas , Animales , Estenosis de la Válvula Aórtica/diagnóstico , Modelos Animales de Enfermedad , Ecocardiografía Transesofágica , Diseño de Equipo , Diseño de Prótesis , Porcinos , Tomografía Computarizada por Rayos X
11.
J Thromb Thrombolysis ; 38(3): 380-7, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24510702

RESUMEN

Factor XIII (FXIII) is necessary for cross linking of fibrin strands and generation of stable fibrin clot. FXIII Val34Leu is a common genetic single nucleotide polymorphism that has been associated with accelerated fibrin stabilization and reduced rate of fibrinolysis. The contribution of Val34Leu to long term risk of recurrent myocardial infarction (MI) in patients with coronary stenting has not been conclusively established. The objective of the study was to examine the effects of Val34Leu on fibrin generation, platelet aggregation, and long term clinical outcomes in patients with coronary artery disease treated with dual antiplatelet therapy. Patients with angiographically documented coronary artery disease who were treated with aspirin and clopidogrel were enrolled (n = 211). Light transmittance aggregometry and plasma fibrin clot formation using thrombelastography (TEG) were determined. Genotyping of Val34Leu was performed using Taqman assay. Clinical events during follow up were recorded. Homozygous carriers of 34 Leu variant had significantly shorter fibrin clot formation time as compared to wild type individuals (TEG K: 1.27 ± 0.3 vs. 1.68 ± 1.1 min, p = 0.011). The Val34Leu variant was associated with gene dose dependent increased risk of MI (log rank, p = 0.002) or occurrence of composite of MI and CV death (log rank, p = 0.005) with highest event rates observed in homozygous carriers of 34 Leu. In summary, FXIII Val34Leu polymorphism was associated with increased rate of fibrin stabilization in homozygous carriers of the variant and may increase risk of recurrent MI and death in patients with angiographically established coronary artery disease treated with dual antiplatelet therapy.


Asunto(s)
Enfermedad de la Arteria Coronaria , Factor XIII , Infarto del Miocardio , Polimorfismo Genético , Adulto , Anciano , Sustitución de Aminoácidos , Aspirina/administración & dosificación , Clopidogrel , Enfermedad de la Arteria Coronaria/sangre , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Enfermedad de la Arteria Coronaria/genética , Factor XIII/genética , Factor XIII/metabolismo , Femenino , Fibrina/genética , Fibrina/metabolismo , Humanos , Masculino , Persona de Mediana Edad , Infarto del Miocardio/sangre , Infarto del Miocardio/tratamiento farmacológico , Infarto del Miocardio/etiología , Infarto del Miocardio/genética , Agregación Plaquetaria/efectos de los fármacos , Agregación Plaquetaria/genética , Inhibidores de Agregación Plaquetaria/administración & dosificación , Tromboelastografía , Ticlopidina/administración & dosificación , Ticlopidina/análogos & derivados
12.
Catheter Cardiovasc Interv ; 83(1): E85-93, 2014 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-23592431

RESUMEN

OBJECTIVES: Ideally, guidewires used during peripheral vasculature (PV) interventions could serve both as a therapy delivery platform and a diagnostic tool for real-time vessel sizing (2-in-1 function). BACKGROUND: Vascular imaging modalities, like intravascular ultrasound (IVUS), used during lower PV interventions, can improve outcomes versus angiographic assessment alone, but are rarely used due to added time, cost, and required clinical training/interpretation. METHODS: A 0.035″ bodied 0.035″ conductance guidewire (CGW) is described here as a vascular navigation and diagnostic real-time PV sizing tool. When attached to a console, the CGW creates a safe, electric field to determine vascular size through simultaneous voltage measurements. RESULTS: The CGW showed functionality as a workhorse guidewire on the bench (torqueability and trackability equivalent to a Wholey guidewire) and in vivo (over-the-wire stent deployment in domestic swine and first-in-man study with no major adverse events). Validation of CGW sizing versus the true diameter and IVUS was completed in 4-10 mm diameter phantoms on the bench and in swine and showed virtually no bias with excellent repeatability and accuracy (i.e., CGW repeatability: swine phantom bias = 0.03 ± 0.09 mm (1.3% error). CGW vs. true diameter: in vivo bias = 0.14 ± 0.15 mm (2.7% error). IVUS vs. true diameter: swine phantom bias = 0.01 ± 0.36 mm (4.7% error). CCW vs. IVUS: swine phantom bias = 0.13 ± 0.26 mm (3.8% error)). CONCLUSIONS: Real-time, accurate, and safe PV dimension assessment and therapy-delivery (2-in-1 function) is possible using a novel workhorse 0.035″ bodied CGW.


Asunto(s)
Cateterismo Periférico/instrumentación , Procedimientos Endovasculares/instrumentación , Enfermedades Vasculares Periféricas/diagnóstico , Enfermedades Vasculares Periféricas/terapia , Ultrasonografía Intervencional/instrumentación , Dispositivos de Acceso Vascular , Animales , Diseño de Equipo , Humanos , Masculino , Ensayo de Materiales , Persona de Mediana Edad , Modelos Animales , Fantasmas de Imagen , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Stents , Sus scrofa , Torque
13.
J Vasc Surg ; 60(3): 759-66, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23992994

RESUMEN

BACKGROUND: Because stent underdeployment occurs frequently, accurate minimal stent area (MSA) measurement during postdilatation is necessary. This study investigated the accuracy and repeatability for MSA determination using a novel conductance balloon (CB) catheter for peripheral vessels. METHODS: The CB catheter is a standard balloon catheter that measures electrical conductance (ratio of current/voltage drop) in real-time during inflation, which directly relates to the balloon cross-sectional area through Ohm's law. CB measurements were made in 4- to 10-mm phantoms on the bench, ex vivo in stents fully deployed in diseased human peripheral arteries, and in vivo in stents fully deployed in peripheral vessels in six swine. CB measurement accuracy and repeatability were calculated and compared with the known dimension (bench phantoms) or with intravascular ultrasound (IVUS) measurement after stent deployment (ex vivo and in vivo). RESULTS: CB measurements were highly accurate (error: 1.8% bench, 5% ex vivo, and 5% in vivo) and repeatable (error: 0.9% bench, 1.8% ex vivo, and 1.3% in vivo), with virtually no bias (average difference in measurements: -0.05 mm bench CB vs known phantom diameters, -0.06 mm ex vivo CB vs IVUS, and -0.11 mm in vivo CB vs IVUS). CONCLUSIONS: The CB sizing capability can be integrated within a standard balloon catheter (two-in-one function) to provide accurate, real-time assessment of MSA to ensure full stent apposition rather than the use of pressure as a surrogate for size.


Asunto(s)
Angioplastia de Balón/instrumentación , Arterias Carótidas , Arteria Ilíaca , Enfermedad Arterial Periférica/terapia , Stents , Dispositivos de Acceso Vascular , Animales , Arterias Carótidas/diagnóstico por imagen , Conductividad Eléctrica , Humanos , Arteria Ilíaca/diagnóstico por imagen , Masculino , Modelos Animales , Enfermedad Arterial Periférica/diagnóstico , Valor Predictivo de las Pruebas , Presión , Diseño de Prótesis , Radiografía , Reproducibilidad de los Resultados , Porcinos , Ultrasonografía Intervencional
14.
Blood Coagul Fibrinolysis ; 24(3): 321-6, 2013 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-23429252

RESUMEN

Inflammation is implicated in the progression of coronary artery disease and the molecular processes of inflammation and thrombosis are closely intertwined. Elevated levels of C-reactive protein (CRP) have been associated with an elevated risk of adverse ischaemic events after coronary stenting and hypercoagulability. Heightened whole blood clot strength measured by thrombelastography (TEG) has been associated with adverse ischaemic events after stenting. We intended to examine the relationship of CRP to plasma fibrin clot strength in patients after coronary stenting. Plasma fibrin clot strength was measured by TEG in 54 patients 16-24 h after undergoing elective percutaneous coronary intervention (PCI). Coagulation was induced in citrated plasma by addition of kaolin and CaCl2. Plasma levels of CRP and fibrinogen were measured by enzyme-linked immunoassay. Increasing quartiles of CRP were associated with increasing levels of maximal plasma fibrin clot strength measured by TEG (P < 0.001) and increasing BMI (P = 0.04). Patients in the highest quartile of CRP had significantly higher maximal fibrin clot strength (G) than the patients in the lowest quartile (G: 3438 ±â€Š623 vs. 2184 ±â€Š576 dyn/cm, P < 0.0001). Fibrinogen concentration was not significantly different across quartiles of CRP (P = 0.97). Patients with established coronary artery disease undergoing coronary stenting who have elevated CRP after PCI exhibit heightened maximal plasma fibrin clot strength as compared with those with low CRP. Thrombotic risk associated with elevated CRP may be linked to procoagulant changes and high tensile fibrin clot strength independent of fibrinogen concentration.


Asunto(s)
Angioplastia Coronaria con Balón , Proteína C-Reactiva/metabolismo , Enfermedad de la Arteria Coronaria/sangre , Fibrina/metabolismo , Trombofilia/sangre , Trombosis/sangre , Anciano , Coagulación Sanguínea , Cloruro de Calcio/química , Enfermedad de la Arteria Coronaria/complicaciones , Enfermedad de la Arteria Coronaria/patología , Enfermedad de la Arteria Coronaria/cirugía , Femenino , Fibrinógeno/metabolismo , Humanos , Inflamación , Caolín/química , Masculino , Persona de Mediana Edad , Factores de Riesgo , Stents , Tromboelastografía , Trombofilia/complicaciones , Trombofilia/patología , Trombofilia/cirugía , Trombosis/complicaciones , Trombosis/patología , Trombosis/cirugía
15.
Thromb Res ; 130(2): 198-202, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22459907

RESUMEN

INTRODUCTION: Clopidogrel inhibits ADP mediated platelet aggregation through inhibition of the P2Y12 receptor by its active metabolite. Thrombin induces platelet aggregation by binding to protease activated receptor-1 (PAR-1), and inhibition of PAR-1 has been evaluated in patients treated with clopidogrel to reduce ischemic events after acute coronary syndromes. Residual PAR-1 mediated platelet aggregation may be dependent on extent of clopidogrel response. MATERIAL AND METHODS: Platelet aggregation was measured in 55 patients undergoing elective PCI at 16-24 hours after 600 mg clopidogrel loading dose by light transmittance aggregometry using ADP 20 µM and thrombin receptor agonist peptide (TRAP) at 15 µM and 25 µM as agonists. Genomic DNA was genotyped for common CYP2C19 variants. RESULTS: Increasing quartiles of 20 µM ADP induced platelet aggregation after clopidogrel loading were associated with increasing levels of TRAP mediated platelet aggregation. Patients in the highest quartile (clopidogrel non-responders) of post treatment ADP aggregation had significantly higher TRAP mediated aggregation than the patients in the lowest quartile (clopidogrel responders) [TRAP 15 µM: 79.6 ± 5% vs. 69.5 ± 8%, p<0.001]. CONCLUSIONS: Non-responders to clopidogrel show increased residual platelet aggregation induced by TRAP, whereas clopidogrel responders exhibit attenuated response to TRAP. Addition of PAR-1 antiplatelet drugs may be most effective in patients with reduced clopidogrel response and high residual TRAP mediated platelet aggregation.


Asunto(s)
Plaquetas/efectos de los fármacos , Intervención Coronaria Percutánea , Inhibidores de Agregación Plaquetaria/uso terapéutico , Agregación Plaquetaria/efectos de los fármacos , Receptor PAR-1/metabolismo , Ticlopidina/análogos & derivados , Anciano , Hidrocarburo de Aril Hidroxilasas/genética , Plaquetas/citología , Clopidogrel , Citocromo P-450 CYP2C19 , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Intervención Coronaria Percutánea/efectos adversos , Inhibidores de Agregación Plaquetaria/farmacología , Receptores de Trombina/metabolismo , Trombosis/prevención & control , Ticlopidina/farmacología , Ticlopidina/uso terapéutico
16.
Am J Physiol Heart Circ Physiol ; 301(6): H2254-63, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21926337

RESUMEN

Stent can cause flow disturbances on the endothelium and compliance mismatch and increased stress on the vessel wall. These effects can cause low wall shear stress (WSS), high wall shear stress gradient (WSSG), oscillatory shear index (OSI), and circumferential wall stress (CWS), which may promote neointimal hyperplasia (IH). The hypothesis is that stent-induced abnormal fluid and solid mechanics contribute to IH. To vary the range of WSS, WSSG, OSI, and CWS, we intentionally mismatched the size of stents to that of the vessel lumen. Stents were implanted in coronary arteries of 10 swine. Intravascular ultrasound (IVUS) was used to size the coronary arteries and stents. After 4 wk of stent implantation, IVUS was performed again to determine the extent of IH. In conjunction, computational models of actual stents, the artery, and non-Newtonian blood were created in a computer simulation to yield the distribution of WSS, WSSG, OSI, and CWS in the stented vessel wall. An inverse relation (R(2) = 0.59, P < 0.005) between WSS and IH was found based on a linear regression analysis. Linear relations between WSSG, OSI, and IH were observed (R(2) = 0.48 and 0.50, respectively, P < 0.005). A linear relation (R(2) = 0.58, P < 0.005) between CWS and IH was also found. More statistically significant linear relations between the ratio of CWS to WSS (CWS/WSS), the products CWS × WSSG and CWS × OSI, and IH were observed (R(2) = 0.67, 0.54, and 0.56, respectively, P < 0.005), suggesting that both fluid and solid mechanics influence the extent of IH. Stents create endothelial flow disturbances and intramural wall stress concentrations, which correlate with the extent of IH formation, and these effects were exaggerated with mismatch of stent/vessel size. These findings reveal the importance of reliable vessel and stent sizing to improve the mechanics on the vessel wall and minimize IH.


Asunto(s)
Angioplastia Coronaria con Balón/efectos adversos , Proliferación Celular , Circulación Coronaria , Reestenosis Coronaria/etiología , Vasos Coronarios/patología , Endotelio Vascular/patología , Stents/efectos adversos , Angioplastia Coronaria con Balón/instrumentación , Animales , Fenómenos Biomecánicos , Simulación por Computador , Reestenosis Coronaria/diagnóstico por imagen , Reestenosis Coronaria/patología , Reestenosis Coronaria/fisiopatología , Vasos Coronarios/diagnóstico por imagen , Vasos Coronarios/fisiopatología , Endotelio Vascular/diagnóstico por imagen , Endotelio Vascular/fisiopatología , Hiperplasia , Modelos Lineales , Masculino , Metales , Modelos Animales , Modelos Cardiovasculares , Diseño de Prótesis , Estrés Mecánico , Porcinos , Ultrasonografía Intervencional
17.
Acute Card Care ; 13(2): 99-108, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21539459

RESUMEN

BACKGROUND: External pumps have been previously used to minimize edema and hemorrhage caused by coronary retroperfusion. The objective of this study was to use a pump-less approach (selective autoretroperfusion, SARP) to preserve myocardial function after acute coronary artery ligation. METHODS: In five experimental pigs, the LAD artery was ligated distal to the first diagonal and retroperfusion was instituted for three hours from a brachiocephalic artery at 50 mmHg pressure through an adjustable occluder on the cannula. In eight control pigs, the LAD artery was ligated distal to the second diagonal for the same duration with no SARP. RESULTS: ECG showed more prominent S-T segment elevation in the untreated control group despite the more distal ligation. The degree of myocardial contraction was significantly attenuated in the control group but was largely preserved in the SARP treated group. The myocytes were well preserved in the SARP group with no rupture of venous microvessels. Myocyte edema and disruption was observed in the control group with only mild extracellular edema in the SARP treated group. CONCLUSION: SARP preserved myocardial function with no damage to the myocyte and venules during three hours of acute LAD ligation.


Asunto(s)
Enfermedad de la Arteria Coronaria/fisiopatología , Corazón/fisiopatología , Reperfusión Miocárdica , Animales , Estudios de Casos y Controles , Enfermedad de la Arteria Coronaria/mortalidad , Vasos Coronarios , Modelos Animales de Enfermedad , Electrocardiografía , Femenino , Ligadura , Masculino , Contracción Miocárdica , Reperfusión Miocárdica/efectos adversos , Reperfusión Miocárdica/métodos , Porcinos , Resultado del Tratamiento
18.
Catheter Cardiovasc Interv ; 78(2): 202-10, 2011 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-20939042

RESUMEN

OBJECTIVES: The objective of this human pilot study was to determine the safety and the level of agreement between a novel nonimaging 2.7 Fr. catheter-based system (LumenRECON, LR) that uses electrical conductance for measurement of lumen cross-sectional area (CSA) with intravascular ultrasound (IVUS) and quantitative coronary angiography (QCA). Based on previous animal studies, we hypothesized the level of agreement between LR and IVUS to be 13%. BACKGROUND: Accurate and reproducible vessel sizing is essential for optimal percutaneous coronary intervention (PCI). METHODS: A total of 12 patients were studied to evaluate the safety, accuracy, and reproducibility of the system in comparison with IVUS and QCA. The CSA of coronary arteries was determined by IVUS, QCA, and LR in the distal, proximal, and center of a lesion during standard PCI. RESULTS: A Bland-Altman plot of the LR versus IVUS and QCA show a nonsignificant mean difference between the two measurements of 0.04 and 0.07 mm in diameter, respectively. The root mean square error of LR versus IVUS and QCA was 14.3 and 25.8% of the mean IVUS or QCA diameter, respectively. The mean of the difference between two LR duplicate measurements was nearly zero (0.03 mm) and the repeatability coefficient was within 8.7% of the mean of the two measurements. There were no procedural complications nor were any device-related MACE reported within 30 days of the procedure. CONCLUSIONS: This proof of concept pilot study establishes the safety and accuracy of the conductance technology for a pivotal trial of coronary sizing.


Asunto(s)
Angioplastia Coronaria con Balón/instrumentación , Cateterismo Cardíaco/instrumentación , Catéteres , Estenosis Coronaria/diagnóstico , Estenosis Coronaria/terapia , Vasos Coronarios/patología , Anciano , Anciano de 80 o más Años , Angioplastia Coronaria con Balón/efectos adversos , Cateterismo Cardíaco/efectos adversos , Angiografía Coronaria , Vasos Coronarios/diagnóstico por imagen , Conductividad Eléctrica , Diseño de Equipo , Femenino , Humanos , Indiana , Masculino , Persona de Mediana Edad , Seguridad del Paciente , Proyectos Piloto , Valor Predictivo de las Pruebas , Reproducibilidad de los Resultados , Medición de Riesgo , Resultado del Tratamiento , Ultrasonografía Intervencional
19.
Am J Cardiol ; 104(12): 1631-7, 2009 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-19962466

RESUMEN

Electrocardiographic signs of a non-ST elevation myocardial infarction (NSTEMI) are nonspecific, and therefore the diagnosis of NSTEMI during acute coronary syndromes (ACS) depends mainly on cardiac biomarker levels. Fragmented QRS (fQRS) represents myocardial conduction abnormalities due to myocardial infarction (MI) scars in patients with coronary artery disease. However, the time of appearance of fQRS during ACS has not been investigated. It was postulated that in patients with ACS, fQRS on 12-lead electrocardiography occurs within 48 hours of presentation with NSTEMI as well as ST elevation MI and that fQRS predicts mortality. Serial electrocardiograms from 896 patients with ACS (mean age 62 +/- 11 years, 98% men) who underwent cardiac catheterization were studied. Four hundred forty-one patients had MIs, including 337 patients with NSTEMIs, and 455 patients had unstable angina (the control group). Serial electrocardiograms were obtained every 6 to 8 hours during the first 24 hours after the diagnosis of MI and the next day (<48 hours). Fragmented QRS on 12-lead electrocardiography was defined by the presence of single or multiple notches in the R or S wave, without a typical bundle branch block, in > or =2 contiguous leads in 1 of the major coronary artery territories. Fragmented QRS developed in 224 patients (51%) in the MI group and only 17 (3.7%) in the control group (p <0.001). New Q waves developed in 122 (28%), 76 (23%), and 2 (0.4%) patients in the MI, NSTEMI, and control groups, respectively. The sensitivity values of fQRS for ST elevation MI and NSTEMI were 55% and 50%, respectively. The specificity of fQRS was 96%. Kaplan-Meier survival analysis revealed that patients with fQRS had significantly decreased times to death compared to those without fQRS. Fragmented QRS, T-wave inversion, and ST depression were independent predictors of mortality during a mean follow-up period of 34 +/- 16 months. In conclusion, fQRS on 12-lead electrocardiography is a moderately sensitive but highly specific sign for ST elevation MI and NSTEMI. Fragmented QRS is an independent predictor of mortality in patients with ACS.


Asunto(s)
Síndrome Coronario Agudo/diagnóstico , Síndrome Coronario Agudo/mortalidad , Electrocardiografía , Infarto del Miocardio/diagnóstico , Infarto del Miocardio/mortalidad , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Valor Predictivo de las Pruebas , Sensibilidad y Especificidad
20.
Am J Physiol Heart Circ Physiol ; 297(1): H485-92, 2009 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-19465543

RESUMEN

Accurate sizing of vessel diameter is important for understanding the physiology of blood vessels as well as the treatment of coronary and peripheral artery disease. The objective of this study was to validate a novel catheter-based system [the LumenRECON (LR) system] for the real-time reconstruction of lumen cross-sectional area (CSA) along the length of a vessel segment. A total of 22 swine (20 Yorkshire and 2 atherosclerotic Ossabaw swine) were used to evaluate the accuracy, reproducibility, and safety of the system compared with intravascular ultrasound (IVUS). The CSA of the right coronary artery, left anterior descending coronary artery, and left circumflex artery were determined by IVUS and the LR system over a 3- to 4-cm segment in 12 Yorkshire and 2 atherosclerotic Ossabaw swine and 2 postmortem atherosclerotic human hearts. In eight chronic animals, the effect of the LR catheter on the vessel wall was evaluated at 1 day and 2 wk (4 animals each) after the intervention. A Bland-Altman plot of the LR and IVUS data showed a mean difference between the two measurements of 0.055 mm in diameter, which was not statistically significant from zero, indicating a lack of bias in the comparison of the LR system with IVUS. The root mean square error of the two measurements was 10.2% of the mean IVUS diameter. The repeatability of the LR system was assessed using duplicate measurements. The mean of the difference between the two measurements was nearly zero, and the repeatability coefficient was within 4.5% of the mean of the two measurements. No injury or intimal hyperplasia was found acutely or chronically after the use of the LR system. This study establishes the accuracy, reproducibility, and safety of a nonimaging 2.7-Fr catheter for lumen sizing of coronary arteries. The system provides a continuous quantitative axial profile of the mean vessel lumen in real time and may have significant utility in vascular research and clinically in the catheterization laboratory.


Asunto(s)
Vasos Coronarios/anatomía & histología , Vasos Coronarios/fisiología , Algoritmos , Animales , Aterosclerosis/genética , Aterosclerosis/patología , Cateterismo , Vasos Coronarios/patología , Electrocardiografía , Hemodinámica/fisiología , Humanos , Procesamiento de Imagen Asistido por Computador , Técnicas In Vitro , Análisis de los Mínimos Cuadrados , Modelos Anatómicos , Fantasmas de Imagen , Reproducibilidad de los Resultados , Porcinos
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